Agricultural Bio-Resources Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou, 350003, Fujian, China.
College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China.
Curr Microbiol. 2020 Aug;77(8):1916-1923. doi: 10.1007/s00284-020-01964-x. Epub 2020 Apr 4.
16S rRNA gene sequence analysis showed that the type strain Brevibacterium frigoritolerans DSM 8801 had the highest similarity (99.7%) with the reference strain Bacillus simplex NBRC 15720, followed by Bacillus muralis DSM 16288 (99.6%), Bacillus butanolivorans DSM 18926 (99.5%), and Bacillus loiseleuriae FJAT-27997 (97.9%). This relationship is confirmed by the phylogenetic analysis indicating that Bre. frigoritolerans DSM 8801 fell in the genus Bacillus group and formed a clade with the closely related Bacillus species. Average nucleotide identity and in silico DNA-DNA hybridization (isDDH) values between strain DSM 8801 and the most closed reference strain Bac. simplex NBRC 15720 were both much lower than species definition threshold values of 95% and 70%, respectively, which indicated strain DSM 8801 should not be affiliated to one of the validly named Bacillus species. The percentage of conserved protein (POCP) values between the strain DSM 8801 and the type strains of the above species were 80.7%, 69.2%, 72.2%, 53.6%, and 50.0%, respectively, higher than the genus definition threshold value of 50%. The main isoprenoid quinone of strain DSM 8801 was MK-7, the main polar lipids were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), and phosphatidyl ethanolamine (PE), and the major fatty acids were anteiso-C and iso-C. On the basis of the phenotypic, chemotaxonomic, phylogenetic and genomic characteristics, Bre. frigoritolerans DSM 8801 should belong to the genus Bacillus, and be proposed to reclassify as Bacillus frigoritolerans comb. nov., with the type strain DSM 8801 (=ATCC 25097 = CCUG 43489= CIP 67.20= JCM 11681).
16S rRNA 基因序列分析表明，模式菌株 Brevibacterium frigoritolerans DSM 8801 与参考菌株 Bacillus simplex NBRC 15720 的相似度最高（99.7%），其次是 Bacillus muralis DSM 16288（99.6%）、Bacillus butanolivorans DSM 18926（99.5%）和 Bacillus loiseleuriae FJAT-27997（97.9%）。系统发育分析证实了这种关系，表明 Bre. frigoritolerans DSM 8801 属于芽孢杆菌属群，并与密切相关的芽孢杆菌种形成一个分支。菌株 DSM 8801 与最接近的参考菌株 Bac. simplex NBRC 15720 之间的平均核苷酸同一性和体外 DNA-DNA 杂交（isDDH）值均远低于 95%和 70%的种定义阈值，这表明菌株 DSM 8801 不应属于已命名的芽孢杆菌种之一。菌株 DSM 8801 与上述种的模式菌株之间的保守蛋白（POCP）值分别为 80.7%、69.2%、72.2%、53.6%和 50.0%，均高于 50%的属定义阈值。菌株 DSM 8801 的主要类异戊二烯醌是 MK-7，主要极性脂是双磷脂酰甘油（DPG）、磷脂酰甘油（PG）和磷脂酰乙醇胺（PE），主要脂肪酸是 anteiso-C 和 iso-C。基于表型、化学分类、系统发育和基因组特征，Bre. frigoritolerans DSM 8801 应属于芽孢杆菌属，并建议重新分类为嗜冷芽孢杆菌 comb. nov.，模式菌株为 DSM 8801（=ATCC 25097=CCUG 43489=CIP 67.20=JCM 11681）。
